Performance Measurement

פירורי לחם

פירורי לחם

Performance Measurement

Jan 28, 2016

Regional Transportation Performance Measurement

CMAP is developing performance measures, internal processes, and partnerships with other agencies to assure that transportation funds are not allocated based on arbitrary formulas, but on performance data. A performance-based funding system will be more likely to identify and mitigate transportation system deficiencies than fixed allocation processes. CMAP is committed to working with implementers to develop a transparent programming process that allocates funding efficiently to maintain a world-class multi-modal transportation system. For more information, see CMAP's summary of the performance-based funding concept. Transportation performance measures and their application to improve the programming processes for the region are key elements of CMAP's Congestion Management Process

Expressway Atlas. In addition to the performance measures below, researchers and the public may be interested in the 2012 Expressway Atlas and its 2014 Update. The Atlas includes system data, daily and monthly factors, AADT tables, hourly percent tables, and detailed traffic flow graphics. The 2014 Update includes updated graphics of the link-by-link and ramp-by-ramp traffic volume estimates using highly detailed corridor-level drawings.

Regional Transportation System Performance Measure Mapping

CMAP has embarked on a project to prepare transportation facility performance datasets for application to performance-based programming. The datasets provide information at the facility level, and span a variety of interest areas, including safety, system preservation, mobility, travel time reliability, and accessibility.

Below are three highway performance maps showing data related to mobility and travel time reliability.

Free-Flow Speeds. The performance maps above rely on a concept of "free-flow travel time" to compare to congested conditions. In the Chicago region, we measured the free-flow travel time based on average speeds from 8 pm to 5:30 am. Free-Flow Speeds, Chicago Region, 2012.

Safety

This performance measure category includes analyses of data on crashes, injuries, and fatalities.

Motor Vehicle Casualties. The measures below show various aspects of the level of motor vehicle casualties. The data is for the seven-county area.

Measure

2002

2005

2008

2009

2010

2011

2012

Fatalities

675

629

438

394

398

371

419

Fatalities per 100 Million VMT

1.15

1.04

0.74

0.67

0.68

0.65

0.72

Fatalities per 100 Thousand Population

8.19

7.59

5.24

4.69

4.72

4.38

4.93

Non-Fatal Injuries

85,810

75,067

61,782

58,556

58,294

56,293

55,838

Non-Fatal Injuries per 100 Million VMT

146

124

105

99

99

99

96

Non-Fatal Injuries per 100 Thousand Population

1,041

906

739

697

691

664

657

Source: CMAP, calculated from IDOT and US Census Bureau Data. 2013 data is expected to be released in late 2014.

System Preservation

This performance measure category includes analyses of data on the maintenance and state of repair for transportation assets in the region.

Ride Quality: Principal Arterials. Acceptable ride quality on the region's highways is measured by the International Roughness Index (IRI). IRI is the change in longitudinal profile, measured as meters per kilometer. The GO TO 2040 target for 2015 is 65%; the year 2040 target is 90%.

Measure

2006

2010

2011

2012

Principal Arterials of Acceptable Ride Quality (IRI < 170)

61.9%

68.5%

70.6%

73.2%

Source: Calculated by CMAP from IDOT Data

Bridge Conditions: Structurally Deficient. "Structurally deficient" is a measure of highway bridge structural health. This information is generated from detailed structural evaluations gathered as part of bridge inspections.

Measure

2001

2006

2009

2010

2011

2012

Structurally Deficient Bridges, Percent of All Bridges

13.5%

10.6%

10.3%

9.8%

9.9%

9.7%

Source: Calculated by CMAP from FHWA National Bridge Inventory Data. The year indicates the year of the file, reflecting data collected through the previous year.

Bridge Conditions: Not Deficient. "Not Deficient" measures highway bridges that are neither "structurally deficient," as shown above, nor "functionally obsolete." The GO TO 2040 target for 2015 is 70%; the year 2040 target is 80%.

Measure

2001

2006

2009

2010

2011

2012

Bridges "Not Deficient," Percent of All Bridges

62.3%

66.9%

67.2%

67.3%

68.3%

68.7%

Source: Calculated by CMAP from FHWA National Bridge Inventory Data

Transit. The above measures originate from periodic system-wide highway asset condition assessments. Such measures do not exist for the transit system. Development of such measures is a priority.

Travel time Reliability

This performance measure category includes analyses of data on the impacts of incidents and daily variation on travel times and the extra time required by travelers to arrive "on time."

Planning Time Index. This is a measure of travel time reliability. It is the ratio of the total time needed to ensure a 95% on-time arrival to the free-flow travel time.

Measure

2007

2008

2009

2010

2011

2012

2015

Planning Time Index, Limited Access Highways, Second Quarter

2.03

1.95

1.72

1.74

1.70

1.65

3.03

Source: Federal Highway Administration.

Average Weekday Motorist Delay at Highway-Rail Grade Crossings. This is a measure of the delay associated with railroad grade crossings. GO TO 2040 established targets of <10,000 hours per weekday by 2015, and <5,500 hours per weekday by 2040.

Measure

2002

2008

2009

2010

2011

2012

Average Weekday Motorist Delay at

Highway-Rail Grade Crossings

10,982

N.A.

N.A.

N.A.

7,817

N.A.

Source: Illinois Commerce Commission. N.A. means "not available."

Metra On-Time Performance. This is a measure of on-time performance of Metra commuter rail services. This is calculated by Metra.

Mobility

This performance measure category includes analyses of data on congestion, travel times, and vehicle miles traveled on the region's transportation networks.

Travel Time Index, Limited Access Highways. This is a measure of congestion. It's defined as the ratio of peak-period travel time to free-flow travel time. Peak-period is 6-9 am and 4-7 pm. Data for individual facilities is on our scans page.

Measure

2007

2008

2009

2010

2011

2012

2015

Travel Time Index, Limited Access Highways, Second Quarter

1.50

1.46

1.32

1.39

1.34

1.32

1.5

Source: Federal Highway Administration

Congested Hours per Day, Limited Access Highways. This measures the number of hours per day during which at least 20% of the vehicle-miles are traveling at congested speeds (less than 45 mph). The GO TO 2040 target is no growth in congested hours. Data for individual facilities is on our scans page.

Measure

2007

2008

2009

2010

2011

2012

2015

Congested Hours per Day, Limited Access Highways, Second Quarter

12.40

13.45

10.05

9.39

8.07

8.38

6.5

Source: Federal Highway Administration

Accessibility

This performance measure category includes analyses of data on both the access of goods and services for economic development and the access of people to institutions and commerce for community development.

Vehicle Miles Traveled (VMT) per Year per Capita (AADT-Based). This measures travel demand. Higher VMT sometimes explains greater congestion. For this measure, IDOT calculates total VMT by factoring traffic counts on regional roads. This measure includes all highway travel, including through trips and external travelers in the region.

Measure

2007

2008

2009

2010

2011

2012

Vehicle Miles Traveled (VMT) per Year per Capita (Traffic Count-Based Measure)